Fluid tight packages



May 17, 1960 M. BERGHGRACHT 2,936,940

'FLUID TIGHT PACKAGES Filed Oct. 26, 1956 Inventor MAR/U5 BERGHGRAC'H T A Ifomay:

States Patent FLUID TIGHT PACKAGES Marius Berghgracht, Gent, Belgium Applicationflctober 26, 1956, Serial No. 618,609

Claims priority, application Belgium October 28, 1955 1 Claim. (Cl. 229-16) The present invention relates to fluid tight packages or containers, more particularly for liquids and powder materials.

The invention more especially relates to a package made in one piece from a blank of pliable material, which is folded in the general form of a hollow body having a polygonal base and tapering towards the opposite end or mouth of the package, the lateral edges of the folded blank being heat sealed. After filling of the package the mouth opening can also be closed by heat sealing, so as to obtain a completely fluid tight package.

A package of this kind has a stable bottom permitting the package to stand in the upright position, although it is made from pliable material. The term pliable material as used herein includes any flexible simple or complex material in sheet form, e.g. paper or cardboard or plastic material, which is capable of being heat sealed, either due to its proper nature or to the fact that it is coated or otherwise covered, at least on the portions which are intended to be heat sealed, with a thermoplastic lacquer or a glue substance whereby two layers of the material can be sealed together in a fluid tight manner by heating.

Known containers of this type have lateral edges or seams in the form of straight lines or interrupted straight lines, whereas score or fold lines can be provided in the side faces for forming angles therein and imparting rigidity to the package and enhancing the appearance thereof, said score lines running from corners of the bottom up to the lateral edges of the container at points located at a substantial distance from the mouth opening.

Experience has. shown that the known containers of this kind have the drawback that undesirable and irregular folds and wrinkles are easily formed, especially in the upper portion, i.e. in the neighbourhood of the mouth opening of the package, this being not only detrimental to the appearance of the package, but also to the fluid tightness thereof, since the said folds and wrinkles initiate cracks in the thermoplastic lacquer or like coating, which result in destroying the fluid tightness of the package.

The object of the invention is to avoid the said disadvantages, while obtaining a'container having a higher mechanical resistance and a more aesthetical appearance.

According to one feature of the invention, the lateral edges or seams of the package are made to follow a curved line, advantageously a continuous curve in the form of a truncated ogive, the term curved line as used in the specification and appended claims, however, also including any line comprising at least one rectilinear portion and at least one curvilinear portion being substantially tangential to said curved portion.

According to a further feature of the invention, the score lines starting from the corners of the bottom are made to extend up to the edges of the mouth opening of the container. s

By way of example, two constructional forms of a 2,936,940 Patented May 17, 1960 package according to, the invention are illustrated in the accompanying diagrammatic drawings, in which:

Figure l is a plan view of a blank from which a container can be obtained by folding and heat sealing of the lateral edges thereof,

Figure 2 shows a perspective view of a container prepared from the said blank, and

Figure 3 is, a perspective view of an alternative form of the container according to the invention. 1

Figure 1 shows a blank cut out from a sheet of pliable material of any convenient nature capable of being heat sealed. The dotted lines are score lines or folding lines along which folding of the blank will be operated in any convenient manner to obtain the container from one single piece of material and including a bottom portion 1, portions 2 and 3 for forming the side faces of the container and lateral portions 4, 5, 6 and 7, the edges or seams whereof will be heat sealed for tightly closing the container. The container in its final form is shown in Figure 2. The sealed seams 8, 9 are formed by the edges of portions 4, 5 and 6, 7 respectively, which have been brought in contact by the folding of the blank and have been heat sealed when in contact. After filling of the container the mouth opening thereof is closed by heat sealing, as shown at 10.

According to the invention, the lateral edges of the blank, and thus of the finished container, have the form of a curved line running from corners of the bottom to the edges of the mouth opening. In the embodiment shown in Figures 1-2, each curved line is a truncated ogive, although other forms can be chosen, as stated above. One possible alternative form is shown in Figure 3, in which the curved line includes two rectilinear portions 11, 12 starting from the corners of the bottom and the mouth opening respectively, and connected by a curvilinear portion 13 which is substantially tangent to the said rectilinear portions. It will be obvious that the curved line can, for instance, also include only one rectilinear portion and one curved portion.

Furthermore, according to the invention, score lines 14, 15 are formed in the blank and result in corresponding angles in the folded container, said score lines extending from corners of the bottom 10 to the edges of the mouth opening of the'container.

The container according to the invention not only has a more aesthetical appearance, but, particularly owing to the combined action of the curved edges and the score lines, it also has an increased resistance and rigidity, thereby avoiding that undesirable folds and wrinkles will be easily formed in the upper portion of the container during handling, storage and transport thereof.

It will be obvious that the invention is not limited to the embodiments as described and illustrated and that, in particular, the form of the curved lateral edges can be modified without departing from the scope of the invention.

I claim:

A fluid tight container having an opening and formed of a single integral piece of foldable sheet material, said container having a non-folded substantially flat rectangular base portion capable of supporting the container in an upright position, said base portion having front, back and side edges; like rectangular front and back panels extending upwardly from said front and back edges on said base portion, respectively; two substantially triangular side panels extending laterally from said front panels and two substantially triangular side panels extending laterally from said back panel, each of said side panels having a bottom edge and a free side edge, the free side said opening thereof, each pair of thus-secured side panels forming a side of the container; two substantially'triangular gusset panels extending upwardly from said side edges of said base portion, respectively; and four additional substantially triangular gusset panels, one of which connects an edge of one of said first-mentioned gusset panels with the bottom edge of a corresponding side panel, said additional gusset panels having free side edges which are interposed between and secured to the lowermost end portions of the free side edges of opposite side panels so that the thus interposed free edges of said additional gusset panels are part of the lowermost end portions of said outstanding fins, said gusset panels together forming 4 r downwardly opening pockets the edges of which lie substantially in the same plane as said base portion.

References Cited in the file of this patent UNITED STATES PATENTS D. 173,718 Cargill et al Dec. 28, 1954 D. 173,933 Cargill et a1. Feb. 1, 1955 2,282,207 Palmer 2 May 5, 1942 2,283,069 Kruetter May 12, 1942 2,401,109 Rohdin May 28, 1946 2,508,962 Moore May 23, 1950 2,821,337 Morgan Ian. 28, 1958 

